The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2008 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ANDROID_SENSORS_INTERFACE_H |
| 18 | #define ANDROID_SENSORS_INTERFACE_H |
| 19 | |
| 20 | #include <stdint.h> |
| 21 | #include <sys/cdefs.h> |
| 22 | #include <sys/types.h> |
| 23 | |
| 24 | #include <hardware/hardware.h> |
Mike Lockwood | 21b652f | 2009-05-22 10:05:48 -0400 | [diff] [blame] | 25 | #include <cutils/native_handle.h> |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 26 | |
| 27 | __BEGIN_DECLS |
| 28 | |
| 29 | /** |
| 30 | * The id of this module |
| 31 | */ |
| 32 | #define SENSORS_HARDWARE_MODULE_ID "sensors" |
| 33 | |
| 34 | /** |
| 35 | * Name of the sensors device to open |
| 36 | */ |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 37 | #define SENSORS_HARDWARE_POLL "poll" |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 38 | |
| 39 | /** |
| 40 | * Handles must be higher than SENSORS_HANDLE_BASE and must be unique. |
| 41 | * A Handle identifies a given sensors. The handle is used to activate |
| 42 | * and/or deactivate sensors. |
| 43 | * In this version of the API there can only be 256 handles. |
| 44 | */ |
| 45 | #define SENSORS_HANDLE_BASE 0 |
| 46 | #define SENSORS_HANDLE_BITS 8 |
| 47 | #define SENSORS_HANDLE_COUNT (1<<SENSORS_HANDLE_BITS) |
| 48 | |
| 49 | |
| 50 | /** |
| 51 | * Sensor types |
| 52 | */ |
| 53 | #define SENSOR_TYPE_ACCELEROMETER 1 |
| 54 | #define SENSOR_TYPE_MAGNETIC_FIELD 2 |
| 55 | #define SENSOR_TYPE_ORIENTATION 3 |
| 56 | #define SENSOR_TYPE_GYROSCOPE 4 |
| 57 | #define SENSOR_TYPE_LIGHT 5 |
| 58 | #define SENSOR_TYPE_PRESSURE 6 |
Mathias Agopian | 54f9dd0 | 2011-03-22 18:42:03 -0700 | [diff] [blame] | 59 | #define SENSOR_TYPE_TEMPERATURE 7 // deprecated |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 60 | #define SENSOR_TYPE_PROXIMITY 8 |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 61 | #define SENSOR_TYPE_GRAVITY 9 |
| 62 | #define SENSOR_TYPE_LINEAR_ACCELERATION 10 |
| 63 | #define SENSOR_TYPE_ROTATION_VECTOR 11 |
Urs Fleisch | d2ed15a | 2010-12-29 17:00:33 +0100 | [diff] [blame] | 64 | #define SENSOR_TYPE_RELATIVE_HUMIDITY 12 |
Mathias Agopian | 54f9dd0 | 2011-03-22 18:42:03 -0700 | [diff] [blame] | 65 | #define SENSOR_TYPE_AMBIENT_TEMPERATURE 13 |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 66 | |
| 67 | /** |
| 68 | * Values returned by the accelerometer in various locations in the universe. |
| 69 | * all values are in SI units (m/s^2) |
| 70 | */ |
| 71 | |
| 72 | #define GRAVITY_SUN (275.0f) |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 73 | #define GRAVITY_EARTH (9.80665f) |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 74 | |
| 75 | /** Maximum magnetic field on Earth's surface */ |
| 76 | #define MAGNETIC_FIELD_EARTH_MAX (60.0f) |
| 77 | |
| 78 | /** Minimum magnetic field on Earth's surface */ |
| 79 | #define MAGNETIC_FIELD_EARTH_MIN (30.0f) |
| 80 | |
| 81 | |
| 82 | /** |
| 83 | * status of each sensor |
| 84 | */ |
| 85 | |
| 86 | #define SENSOR_STATUS_UNRELIABLE 0 |
| 87 | #define SENSOR_STATUS_ACCURACY_LOW 1 |
| 88 | #define SENSOR_STATUS_ACCURACY_MEDIUM 2 |
| 89 | #define SENSOR_STATUS_ACCURACY_HIGH 3 |
| 90 | |
| 91 | /** |
| 92 | * Definition of the axis |
| 93 | * ---------------------- |
| 94 | * |
| 95 | * This API is relative to the screen of the device in its default orientation, |
| 96 | * that is, if the device can be used in portrait or landscape, this API |
| 97 | * is only relative to the NATURAL orientation of the screen. In other words, |
| 98 | * the axis are not swapped when the device's screen orientation changes. |
| 99 | * Higher level services /may/ perform this transformation. |
| 100 | * |
| 101 | * x<0 x>0 |
| 102 | * ^ |
| 103 | * | |
| 104 | * +-----------+--> y>0 |
| 105 | * | | |
| 106 | * | | |
| 107 | * | | |
| 108 | * | | / z<0 |
| 109 | * | | / |
| 110 | * | | / |
| 111 | * O-----------+/ |
| 112 | * |[] [ ] []/ |
| 113 | * +----------/+ y<0 |
| 114 | * / |
| 115 | * / |
| 116 | * |/ z>0 (toward the sky) |
| 117 | * |
| 118 | * O: Origin (x=0,y=0,z=0) |
| 119 | * |
| 120 | * |
| 121 | * Orientation |
| 122 | * ----------- |
| 123 | * |
| 124 | * All values are angles in degrees. |
| 125 | * |
Mathias Agopian | 66a4095 | 2010-07-22 17:11:50 -0700 | [diff] [blame] | 126 | * Orientation sensors return sensor events for all 3 axes at a constant |
| 127 | * rate defined by setDelay(). |
| 128 | * |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 129 | * azimuth: angle between the magnetic north direction and the Y axis, around |
| 130 | * the Z axis (0<=azimuth<360). |
| 131 | * 0=North, 90=East, 180=South, 270=West |
| 132 | * |
| 133 | * pitch: Rotation around X axis (-180<=pitch<=180), with positive values when |
| 134 | * the z-axis moves toward the y-axis. |
| 135 | * |
| 136 | * roll: Rotation around Y axis (-90<=roll<=90), with positive values when |
Mathias Agopian | 19ea59f | 2010-02-26 13:15:18 -0800 | [diff] [blame] | 137 | * the x-axis moves towards the z-axis. |
| 138 | * |
| 139 | * Note: For historical reasons the roll angle is positive in the clockwise |
| 140 | * direction (mathematically speaking, it should be positive in the |
| 141 | * counter-clockwise direction): |
| 142 | * |
| 143 | * Z |
| 144 | * ^ |
| 145 | * (+roll) .--> | |
| 146 | * / | |
| 147 | * | | roll: rotation around Y axis |
| 148 | * X <-------(.) |
| 149 | * Y |
| 150 | * note that +Y == -roll |
| 151 | * |
| 152 | * |
| 153 | * |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 154 | * Note: This definition is different from yaw, pitch and roll used in aviation |
| 155 | * where the X axis is along the long side of the plane (tail to nose). |
| 156 | * |
| 157 | * |
| 158 | * Acceleration |
| 159 | * ------------ |
| 160 | * |
| 161 | * All values are in SI units (m/s^2) and measure the acceleration of the |
| 162 | * device minus the force of gravity. |
| 163 | * |
Mathias Agopian | 66a4095 | 2010-07-22 17:11:50 -0700 | [diff] [blame] | 164 | * Acceleration sensors return sensor events for all 3 axes at a constant |
| 165 | * rate defined by setDelay(). |
| 166 | * |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 167 | * x: Acceleration minus Gx on the x-axis |
| 168 | * y: Acceleration minus Gy on the y-axis |
| 169 | * z: Acceleration minus Gz on the z-axis |
| 170 | * |
| 171 | * Examples: |
| 172 | * When the device lies flat on a table and is pushed on its left side |
| 173 | * toward the right, the x acceleration value is positive. |
| 174 | * |
| 175 | * When the device lies flat on a table, the acceleration value is +9.81, |
| 176 | * which correspond to the acceleration of the device (0 m/s^2) minus the |
| 177 | * force of gravity (-9.81 m/s^2). |
| 178 | * |
| 179 | * When the device lies flat on a table and is pushed toward the sky, the |
| 180 | * acceleration value is greater than +9.81, which correspond to the |
| 181 | * acceleration of the device (+A m/s^2) minus the force of |
| 182 | * gravity (-9.81 m/s^2). |
| 183 | * |
| 184 | * |
| 185 | * Magnetic Field |
| 186 | * -------------- |
| 187 | * |
| 188 | * All values are in micro-Tesla (uT) and measure the ambient magnetic |
| 189 | * field in the X, Y and Z axis. |
Mike Lockwood | a241431 | 2009-11-03 10:29:50 -0500 | [diff] [blame] | 190 | * |
Mathias Agopian | 66a4095 | 2010-07-22 17:11:50 -0700 | [diff] [blame] | 191 | * Magnetic Field sensors return sensor events for all 3 axes at a constant |
| 192 | * rate defined by setDelay(). |
| 193 | * |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 194 | * Gyroscope |
| 195 | * --------- |
| 196 | * All values are in radians/second and measure the rate of rotation |
| 197 | * around the X, Y and Z axis. The coordinate system is the same as is |
Mathias Agopian | c04e5f6 | 2010-09-14 10:53:55 -0700 | [diff] [blame] | 198 | * used for the acceleration sensor. Rotation is positive in the |
| 199 | * counter-clockwise direction (right-hand rule). That is, an observer |
| 200 | * looking from some positive location on the x, y or z axis at a device |
| 201 | * positioned on the origin would report positive rotation if the device |
| 202 | * appeared to be rotating counter clockwise. Note that this is the |
| 203 | * standard mathematical definition of positive rotation and does not agree |
| 204 | * with the definition of roll given earlier. |
| 205 | * The range should at least be 17.45 rad/s (ie: ~1000 deg/s). |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 206 | * |
Mike Lockwood | a241431 | 2009-11-03 10:29:50 -0500 | [diff] [blame] | 207 | * Proximity |
| 208 | * --------- |
| 209 | * |
| 210 | * The distance value is measured in centimeters. Note that some proximity |
| 211 | * sensors only support a binary "close" or "far" measurement. In this case, |
| 212 | * the sensor should report its maxRange value in the "far" state and a value |
| 213 | * less than maxRange in the "near" state. |
| 214 | * |
Mathias Agopian | 478994a | 2010-07-23 17:23:43 -0700 | [diff] [blame] | 215 | * Proximity sensors report a value only when it changes and each time the |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 216 | * sensor is enabled. |
Mathias Agopian | 66a4095 | 2010-07-22 17:11:50 -0700 | [diff] [blame] | 217 | * |
Mike Lockwood | a241431 | 2009-11-03 10:29:50 -0500 | [diff] [blame] | 218 | * Light |
| 219 | * ----- |
| 220 | * |
| 221 | * The light sensor value is returned in SI lux units. |
| 222 | * |
Mathias Agopian | 478994a | 2010-07-23 17:23:43 -0700 | [diff] [blame] | 223 | * Light sensors report a value only when it changes and each time the |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 224 | * sensor is enabled. |
Mathias Agopian | 66a4095 | 2010-07-22 17:11:50 -0700 | [diff] [blame] | 225 | * |
Mathias Agopian | 1832f55 | 2010-07-29 15:22:30 -0700 | [diff] [blame] | 226 | * Pressure |
| 227 | * -------- |
| 228 | * |
| 229 | * The pressure sensor value is returned in hectopascal (hPa) |
| 230 | * |
| 231 | * Pressure sensors report events at a constant rate defined by setDelay(). |
| 232 | * |
Makarand Karvekar | 3120b58 | 2010-08-11 15:10:10 -0700 | [diff] [blame] | 233 | * Gyro |
| 234 | * -------- |
| 235 | * |
| 236 | * The gyroscope sensor values are returned in degrees per second (dps) |
| 237 | * |
| 238 | * Gyroscope sensor report events at a constant rate defined by setDelay(). |
| 239 | * |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 240 | * Gravity |
| 241 | * ------- |
| 242 | * A gravity output indicates the direction of and magnitude of gravity in the devices's |
| 243 | * coordinates. On Earth, the magnitude is 9.8. Units are m/s^2. The coordinate system |
| 244 | * is the same as is used for the acceleration sensor. |
Mathias Agopian | 42b743c | 2010-11-22 15:55:32 -0800 | [diff] [blame] | 245 | * When the device is at rest, the output of the gravity sensor should be identical |
| 246 | * to that of the accelerometer. |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 247 | * |
| 248 | * Linear Acceleration |
| 249 | * ------------------- |
| 250 | * Indicates the linear acceleration of the device in device coordinates, not including gravity. |
| 251 | * This output is essentially Acceleration - Gravity. Units are m/s^2. The coordinate system is |
| 252 | * the same as is used for the acceleration sensor. |
Mathias Agopian | 42b743c | 2010-11-22 15:55:32 -0800 | [diff] [blame] | 253 | * The output of the accelerometer, gravity and linear-acceleration sensors must obey the |
| 254 | * following relation: |
| 255 | * |
| 256 | * acceleration = gravity + linear-acceleration |
| 257 | * |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 258 | * |
| 259 | * Rotation Vector |
| 260 | * --------------- |
| 261 | * A rotation vector represents the orientation of the device as a combination |
| 262 | * of an angle and an axis, in which the device has rotated through an angle |
| 263 | * theta around an axis <x, y, z>. The three elements of the rotation vector |
| 264 | * are <x*sin(theta/2), y*sin(theta/2), z*sin(theta/2)>, such that the magnitude |
| 265 | * of the rotation vector is equal to sin(theta/2), and the direction of the |
| 266 | * rotation vector is equal to the direction of the axis of rotation. The three |
| 267 | * elements of the rotation vector are equal to the last three components of a |
| 268 | * unit quaternion <cos(theta/2), x*sin(theta/2), y*sin(theta/2), z*sin(theta/2)>. |
| 269 | * Elements of the rotation vector are unitless. The x, y, and z axis are defined |
| 270 | * in the same was as for the acceleration sensor. |
Mathias Agopian | 42b743c | 2010-11-22 15:55:32 -0800 | [diff] [blame] | 271 | * |
Mathias Agopian | d93ff97 | 2011-05-02 19:10:31 -0700 | [diff] [blame] | 272 | * The reference coordinate system is defined as a direct orthonormal basis, |
| 273 | * where: |
| 274 | * |
| 275 | * - X is defined as the vector product Y.Z (It is tangential to |
| 276 | * the ground at the device's current location and roughly points East). |
| 277 | * |
| 278 | * - Y is tangential to the ground at the device's current location and |
| 279 | * points towards the magnetic North Pole. |
| 280 | * |
| 281 | * - Z points towards the sky and is perpendicular to the ground. |
| 282 | * |
| 283 | * |
Mathias Agopian | 42b743c | 2010-11-22 15:55:32 -0800 | [diff] [blame] | 284 | * The rotation-vector is stored as: |
| 285 | * |
| 286 | * sensors_event_t.data[0] = x*sin(theta/2) |
| 287 | * sensors_event_t.data[1] = y*sin(theta/2) |
| 288 | * sensors_event_t.data[2] = z*sin(theta/2) |
| 289 | * sensors_event_t.data[3] = cos(theta/2) |
| 290 | * |
Jean-Baptiste Queru | 6e17d2c | 2011-05-18 16:40:03 -0700 | [diff] [blame] | 291 | * |
Urs Fleisch | d2ed15a | 2010-12-29 17:00:33 +0100 | [diff] [blame] | 292 | * Relative Humidity |
| 293 | * ----------------- |
| 294 | * |
| 295 | * A relative humidity sensor measures relative ambient air humidity and |
| 296 | * returns a value in percent. |
| 297 | * |
| 298 | * Relative humidity sensors report a value only when it changes and each |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 299 | * time the sensor is enabled. |
Jean-Baptiste Queru | 6e17d2c | 2011-05-18 16:40:03 -0700 | [diff] [blame] | 300 | * |
| 301 | * |
Mathias Agopian | 54f9dd0 | 2011-03-22 18:42:03 -0700 | [diff] [blame] | 302 | * Ambient Temperature |
| 303 | * ------------------- |
| 304 | * |
| 305 | * The ambient (room) temperature in degree Celsius. |
| 306 | * |
| 307 | * Temperature sensors report a value only when it changes and each time the |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 308 | * sensor is enabled. |
Mathias Agopian | 54f9dd0 | 2011-03-22 18:42:03 -0700 | [diff] [blame] | 309 | * |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 310 | */ |
Kevin Powell | b01a043 | 2010-07-19 19:12:15 -0700 | [diff] [blame] | 311 | |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 312 | typedef struct { |
| 313 | union { |
| 314 | float v[3]; |
| 315 | struct { |
| 316 | float x; |
| 317 | float y; |
| 318 | float z; |
| 319 | }; |
| 320 | struct { |
| 321 | float azimuth; |
| 322 | float pitch; |
| 323 | float roll; |
| 324 | }; |
| 325 | }; |
| 326 | int8_t status; |
| 327 | uint8_t reserved[3]; |
| 328 | } sensors_vec_t; |
| 329 | |
| 330 | /** |
| 331 | * Union of the various types of sensor data |
| 332 | * that can be returned. |
| 333 | */ |
Mathias Agopian | cdefccd | 2010-07-15 18:29:03 -0700 | [diff] [blame] | 334 | typedef struct sensors_event_t { |
| 335 | /* must be sizeof(struct sensors_event_t) */ |
| 336 | int32_t version; |
| 337 | |
| 338 | /* sensor identifier */ |
| 339 | int32_t sensor; |
| 340 | |
| 341 | /* sensor type */ |
| 342 | int32_t type; |
| 343 | |
| 344 | /* reserved */ |
| 345 | int32_t reserved0; |
| 346 | |
| 347 | /* time is in nanosecond */ |
| 348 | int64_t timestamp; |
| 349 | |
| 350 | union { |
| 351 | float data[16]; |
| 352 | |
| 353 | /* acceleration values are in meter per second per second (m/s^2) */ |
| 354 | sensors_vec_t acceleration; |
| 355 | |
| 356 | /* magnetic vector values are in micro-Tesla (uT) */ |
| 357 | sensors_vec_t magnetic; |
| 358 | |
| 359 | /* orientation values are in degrees */ |
| 360 | sensors_vec_t orientation; |
| 361 | |
Mathias Agopian | c04e5f6 | 2010-09-14 10:53:55 -0700 | [diff] [blame] | 362 | /* gyroscope values are in rad/s */ |
| 363 | sensors_vec_t gyro; |
Makarand Karvekar | 3120b58 | 2010-08-11 15:10:10 -0700 | [diff] [blame] | 364 | |
Mathias Agopian | cdefccd | 2010-07-15 18:29:03 -0700 | [diff] [blame] | 365 | /* temperature is in degrees centigrade (Celsius) */ |
| 366 | float temperature; |
| 367 | |
| 368 | /* distance in centimeters */ |
| 369 | float distance; |
| 370 | |
| 371 | /* light in SI lux units */ |
| 372 | float light; |
Mathias Agopian | 1832f55 | 2010-07-29 15:22:30 -0700 | [diff] [blame] | 373 | |
| 374 | /* pressure in hectopascal (hPa) */ |
| 375 | float pressure; |
Urs Fleisch | d2ed15a | 2010-12-29 17:00:33 +0100 | [diff] [blame] | 376 | |
| 377 | /* relative humidity in percent */ |
| 378 | float relative_humidity; |
Mathias Agopian | cdefccd | 2010-07-15 18:29:03 -0700 | [diff] [blame] | 379 | }; |
| 380 | uint32_t reserved1[4]; |
| 381 | } sensors_event_t; |
| 382 | |
| 383 | |
| 384 | |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 385 | struct sensor_t; |
| 386 | |
| 387 | /** |
| 388 | * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM |
| 389 | * and the fields of this data structure must begin with hw_module_t |
| 390 | * followed by module specific information. |
| 391 | */ |
| 392 | struct sensors_module_t { |
| 393 | struct hw_module_t common; |
| 394 | |
| 395 | /** |
| 396 | * Enumerate all available sensors. The list is returned in "list". |
| 397 | * @return number of sensors in the list |
| 398 | */ |
| 399 | int (*get_sensors_list)(struct sensors_module_t* module, |
| 400 | struct sensor_t const** list); |
| 401 | }; |
| 402 | |
| 403 | struct sensor_t { |
| 404 | /* name of this sensors */ |
| 405 | const char* name; |
| 406 | /* vendor of the hardware part */ |
| 407 | const char* vendor; |
| 408 | /* version of the hardware part + driver. The value of this field is |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 409 | * left to the implementation and doesn't have to be monotonically |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 410 | * increasing. |
| 411 | */ |
| 412 | int version; |
| 413 | /* handle that identifies this sensors. This handle is used to activate |
| 414 | * and deactivate this sensor. The value of the handle must be 8 bits |
| 415 | * in this version of the API. |
| 416 | */ |
| 417 | int handle; |
| 418 | /* this sensor's type. */ |
| 419 | int type; |
| 420 | /* maximaum range of this sensor's value in SI units */ |
| 421 | float maxRange; |
| 422 | /* smallest difference between two values reported by this sensor */ |
| 423 | float resolution; |
| 424 | /* rough estimate of this sensor's power consumption in mA */ |
| 425 | float power; |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 426 | /* minimum delay allowed between events in microseconds. A value of zero |
| 427 | * means that this sensor doesn't report events at a constant rate, but |
| 428 | * rather only when a new data is available */ |
| 429 | int32_t minDelay; |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 430 | /* reserved fields, must be zero */ |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 431 | void* reserved[8]; |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 432 | }; |
| 433 | |
| 434 | |
| 435 | /** |
| 436 | * Every device data structure must begin with hw_device_t |
| 437 | * followed by module specific public methods and attributes. |
| 438 | */ |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 439 | struct sensors_poll_device_t { |
| 440 | struct hw_device_t common; |
| 441 | |
| 442 | /** Activate/deactivate one sensor. |
| 443 | * |
| 444 | * @param handle is the handle of the sensor to change. |
| 445 | * @param enabled set to 1 to enable, or 0 to disable the sensor. |
| 446 | * |
| 447 | * @return 0 on success, negative errno code otherwise |
| 448 | */ |
| 449 | int (*activate)(struct sensors_poll_device_t *dev, |
| 450 | int handle, int enabled); |
| 451 | |
| 452 | /** |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 453 | * Set the delay between sensor events in nanoseconds for a given sensor. |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 454 | * |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 455 | * It is an error to set a delay inferior to the value defined by |
Mathias Agopian | 15879d8 | 2011-11-01 19:17:58 -0700 | [diff] [blame^] | 456 | * sensor_t::minDelay. |
| 457 | * |
| 458 | * If sensor_t::minDelay is zero, setDelay() returns an error if the |
| 459 | * requested delay is inferior to 1ms. |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 460 | * |
| 461 | * @return 0 if successful, < 0 on error |
| 462 | */ |
| 463 | int (*setDelay)(struct sensors_poll_device_t *dev, |
| 464 | int handle, int64_t ns); |
| 465 | |
| 466 | /** |
| 467 | * Returns an array of sensor data. |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 468 | * This function must block until events are available. |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 469 | * |
| 470 | * @return the number of events read on success, or -errno in case of an error. |
Mathias Agopian | 1511e20 | 2010-07-29 15:33:22 -0700 | [diff] [blame] | 471 | * This function should never return 0 (no event). |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 472 | * |
| 473 | */ |
| 474 | int (*poll)(struct sensors_poll_device_t *dev, |
Mathias Agopian | cdefccd | 2010-07-15 18:29:03 -0700 | [diff] [blame] | 475 | sensors_event_t* data, int count); |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 476 | }; |
| 477 | |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 478 | /** convenience API for opening and closing a device */ |
| 479 | |
Mathias Agopian | b1e212e | 2010-07-08 16:44:54 -0700 | [diff] [blame] | 480 | static inline int sensors_open(const struct hw_module_t* module, |
| 481 | struct sensors_poll_device_t** device) { |
| 482 | return module->methods->open(module, |
| 483 | SENSORS_HARDWARE_POLL, (struct hw_device_t**)device); |
| 484 | } |
| 485 | |
| 486 | static inline int sensors_close(struct sensors_poll_device_t* device) { |
| 487 | return device->common.close(&device->common); |
| 488 | } |
| 489 | |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 490 | __END_DECLS |
| 491 | |
The Android Open Source Project | f53ebec | 2009-03-03 19:32:14 -0800 | [diff] [blame] | 492 | #endif // ANDROID_SENSORS_INTERFACE_H |